GPS Receiver Module Invalid Data Problem

Hello guys , I have this GPS Module Maker Studio GPS Module

I use Mega 2560 arduino , and I am trying to get the following data from this GPS receiver module :

1-Longitude 2-Latitude 3-Time etc...

the problem is when I turn on the circuit , the Longitude and latitude and time are invalid for a certain time , maybe 2-3 minutes then , only time is valid ( shows the real time ) , but latitude and longitude are still invalid.

Sometimes the longitude and latitude become valid and shows data .

knowing that I am working at the roof.

Any ideas please

You're not seeing enough satellites to get a fix. You need three to get lat/long, four to get lat/long/alt. With one satellite, you'll only get the time. You didn't post the code (sigh)... Does it display the number of satellites?

If there are no other obstructions (tall buildings, trees), it could be an antenna problem or how the antenna is positioned. It should be flat, none of its metal parts should be touching other metal. Move it away from the Arduino and USB cable, make sure the connector is seated, and make sure the connecting wire is not kinked or damaged.

Cheers, /dev

First of all thank you very much :wink: for your reply…and I am sorry that I have been late to send out this reply , but I was trying to have another trials , so that I can answer some of your inquiries.

I uploaded with this reply , the COM port data for 3 trials:

1st trial , I used the DeviceExample code ( it comes with TinyGPS+ libraby)

2nd trial , the same as 1st trial

3rd trial , I used the KitchenSink code ( also it comes with TinyGPS+ library )

I have noticed many things , first of all it takes about 1 to 1.5 minutes to get data about time , then about some seconds to get the date , then about 1.5 to 2.5 minutes to get the Longitude and Latitude.

I have also noticed with the KitchenSink code , that the Altitude is 56 meters , then when I moved a little bit , the Altitude get 57,58,59,60,61 etc uptill 70… knowing that I am still at the same Height(Altitude).

I need to know some info about having Altitude Data from this GPS Module.

Thank you very much :sweat_smile: , I know that I’ve talked too much.

1st time trial with kitchensink Code.pdf (210 KB)

First time trial with device examle code.pdf (225 KB)

Second Time Trial with device example code.pdf (143 KB)

longjump:
… it takes about 1 to 1.5 minutes to get time, then some seconds to get date, then about 1.5 to 2.5 minutes to get the Longitude and Latitude.

Those aren’t unreasonable times at all. I don’t see a backup battery on that shield, so the GPS module has to re-acquire everything when it powers on. 10 minutes isn’t unusual.

I have also noticed with the KitchenSink code , that the Altitude is 56 meters , then when I moved a little bit , the Altitude get 57,58,59,60,61 etc uptill 70… knowing that I am still at the same Height(Altitude).

Yes, the position and altitude data wanders even if you’re stationary. It’s because the satellites move or go out of view, and new ones come in to view. Over a long period of time (hours at a minimum), the average of all the readings converges to a more-accurate fix. Your data shows that you can only see 7 satellites. That’s not great, but it’s good enough to get a 3D fix.

Cheers,
/dev

Thank you for your reply.

Thanks for info.

So it's normal for about 10 min.

Would you plz tell me why I see only 7 satellites , knowing that I am at the roof of my house.

With respect to the Altitude , I've bought a pressure sensor to work as Altimeter , but the same problem happens , that when I move with the sensor , it shows different data.

If this is normal , what sensor I can work with to have a static real altitude.

Thank you for your time .